International Collaboration in Chemistry: A New Molecular Architecture for Organic Electronics

在这个合作项目中，我们专注于基于有机半导体在纳米级器件上有组织生长的新分子结构，通过使用有机金属络合物连接剂定向垂直堆叠双功能低聚芳烃。特别地，将在二氧化硅/硅衬底上生长一层致密的、有组织的双膦酸硫代噻吩单分子层。有组织的垂直生长将通过将该单层暴露于简单有机金属的蒸气中，作为双膦酸盐第二层生长的成核点而开始。这一过程将重复进行，直到生长出足够数量的分子层，以关闭新型硅基晶体管平台中电极-电极纳米级的间隙。本文提出，在硫代噻吩半导体集成中实现高度的分子有序，以实现高度的垂直和横向载流子迁移率。将对双膦酸并五苯进行一系列类似的研究。在功能化协议被转移到纳米结构器件之前，将使用不同的表面分析技术来表征生长的堆叠分子层。最后，将研究新型混合分子器件的电子输运特性（晶体管特性：I-V、转移特性、跨导），以及硅和氧化硅材料特性、通道长度、栅极电压、温度和入射光（光导率）的函数。在项目的后期阶段，堆叠层的性噻吩部分将在化学结构和电子功能上发生变化，以将这些典型的p型导体转换为n型导体。

In this cooperative project, we focus on new molecular architectures based on organized growth of organic semiconductors on nanoscale devices through directed vertical stacking of bifunctional oligoarenes using organometallic complex linkers. In particular, a dense, organized monolayer of sexithiophene bisphosphonate will be grown on a silicon dioxide/silicon substrate. Organized vertical growth will be initiated by exposure of this monolayer to vapor of a simple organometallic to serve as a nucleation site for the growth of a second layer of the bisphosphonate. This process will be repeated until growth of a sufficient number of molecular layers has been achieved to close the electrode-electrode nanoscale gap in novel silicon-based transistor platforms. It is proposed that a high degree of molecular order will be realized in the sexithiophene semiconductor ensemble to enable a high degree of vertical and lateral carrier mobility. A similar series of investigations will be done on pentacene bisphosphonates. The grown stacked molecular layers will be characterized using different surface analysis techniques, before the functionalization protocol is to be transferred onto the nanostructured devices. Finally, the novel hybrid molecular devices will be investigated regarding their electronic transport properties (transistor characteristics: I-V, transfer characteristics, transconductance), as function of silicon and silicon-oxide material properties, channel length, gate voltage, temperature and incident light (photoconductivity). At a later stage of the project the sexithiophene moieties of the stacked layers will be varied in chemical structure and electronic functionality to convert these typically p-type conductors to n-type ones.